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задача 1)AB = 8 см, угол AOC = 60 градусов. найдитe BC.(рис.1)

задача 2)AC=9cм, угол ABC=60 градусов, AO=R найдитe AO.(рис.2)

ПРОВЕРЬТЕ СОЧИНЕНИЕ

Technologies in my life.

It's 21st century now and this is a century of high technologies. There're tons of smartphones, notebooks, tablets etc. which help me to communicate with people. I can get instant access to anything I want due to the internet and that's really simplify my life. I spend my free time using my computer it's kind of for fun. Because of the technologies particularly internet I can easily get skills that are necessary in the information age. It's just so easy all you have to do is just to push buttons to get whatever you want. I rely on technologies too much I trust them. I cannot imagine my life without all that stuff. But sometimes if we use all those gadgets too much we can get in deep troubles, unfortunately. 

При востановлении 40 г оксида меди II оксидом углерода II было получено 28г меди. Чему равна массовая доля выхода продукта реакции?

"Последствия монгольского нашествия для Руси" экономические, политические, культурные последствия